Adobe 23101335 Scripting Guide - Page 10

Photoshop 7.0 Scripting Guide

10

Scripting basics

Object model concepts

2

2.2.2 Object inheritance

Object classes may also “inherit,” or share, the properties of a parent, or superclass. When a

class inherits properties, we call that class a child, or subclass of the class from which it

inherits properties. So in our house example, windows and doors are subclasses of an openings

class, since they are both openings in a house. In Photoshop, art layers, for example, inherit

from the layer class.

Classes will often have properties that aren’t shared with their superclass. In our house, both a

window and door inherit an opened property from the opening class, but a window has a

number of panes property which the Opening class doesn’t. In Photoshop, art layers, for

example, have the property grouped which isn’t inherited from the Layer class.

2.2.3 Object elements or collections

Object elements (AppleScript) or collections (Visual Basic, JavaScript) are objects contained

within other objects. For example, rooms are elements (or collections) of our house, contained

within the house object. In Photoshop, documents are elements of the application object, and

layers are elements of a document object. To access an element (or member of a collection),

you use an index. For example, to get the first document of the application you write:

AS:

document 1

VB:

appRef.Documents (1)

JS:

documents[0];

IMPORTANT:

Indices in AppleScript and Visual Basic are 1 based. JavaScript indicies are 0

based.

2.2.4 Object reference

The objects in your documents are arranged in a hierarchy like the house object — layers are

in layer sets, which are inside a document which is inside Photoshop. When you send a

command to a Photoshop object, you need to make sure you send the message to the right

object. To do this, you identify objects by their position in the hierarchy — by an object

reference. You might, for example, write the following statement.

AppleScript

layer 1 of layer set 1 of current document

Visual Basic

appRef.ActiveDocument.LayerSets(1).Layers(1)

JavaScript

activeDocument.layerSets[0].layers[0];

Section	Page
Photoshop 7.0 Scripting Guide	1
Table of contents	3
Introduction	5
1.1 About this manual	5
1.1.1 Conventions in this guide	5
1.2 What is scripting?	6
1.3 Why use scripting?	6
1.4 What about actions?	6
1.5 System requirements	6
1.5.1 Mac	7
1.5.2 Windows	7
1.6 JavaScript	7
1.7 Choosing a scripting language	7
1.8 Legacy COM scripting	8
Scripting basics	9
2.1 Documents as objects	9
2.2 Object model concepts	9
2.2.1 Object classes	9
2.2.2 Object inheritance	10
2.2.3 Object elements or collections	10
2.2.4 Object reference	10
2.3 Documenting scripts	11
2.4 Values	12
2.5 Variables	14
2.5.1 Assigning values to variables	14
2.5.2 Using variables to store references	15
2.5.3 Naming variables	15
2.6 Operators	16
2.7 Commands and methods	17
2.7.1 Conditional statements	17
2.7.2 Control structures	18
2.8 Handlers, subroutines and functions	20
2.9 The Scripts menu	21
2.9.1 Scripts folder	21
2.9.2 The scripts dialog box	21
2.10 Testing and troubleshooting	23
2.10.1 AppleScript debugging	23
2.10.2 Visual Basic debugging	25
2.10.3 JavaScript Debugging	26
2.10.4 Error handling	31
Scripting Photoshop	33
3.1 Photoshop scripting guidelines	33
3.2 Viewing Photoshop objects, commands and methods	34
3.2.1 Viewing Photoshop’s AppleScript dictionary	34
3.2.2 Viewing Photoshop’s type library (VB)	35
3.3 Your first Photoshop script	36
3.3.1 AppleScript	36
3.3.2 Visual Basic	37
3.3.3 VBScript	39
3.3.4 JavaScript	41
3.4 Object references	42
3.4.1 AppleScript	42
3.4.2 Visual Basic and JavaScript	43
3.5 Working with units	44
3.5.1 Unit values	44
3.5.2 Unit value useage	46
3.5.3 Changing ruler and type units	48
3.6 Executing JavaScripts from AS or VB	48
3.6.1 Passing arguments to JavaScript	49
3.6.2 Executing one-line JavaScripts	50
3.7 The Application object	50
3.8 Document object	54
3.8.1 Saving documents and save options	55
3.8.2 Document information	56
3.8.3 Document manipulation	57
3.9 Layer objects	58
3.9.1 Setting the Active layer	61
3.9.2 Layer sets	61
3.9.3 Linking layers	62
3.9.4 Applying styles to layers	63
3.9.5 Rotating layers	63
3.10 Text item object	64
3.10.1 Setting the contents of the text item	65
3.10.2 Setting text stroke colors	66
3.10.3 Setting fonts	66
3.10.4 Warping text	67
3.11 Selections	67
3.11.1 Defining selections	68
3.11.2 Stroking the selection border	69
3.11.3 Inverting selections	70
3.11.4 Expand, contract and feather selections	70
3.11.5 Filling a selection	71
3.11.6 Rotating selections	72
3.11.7 Loading and storing selections	73
3.12 Working with Filters	74
3.12.1 Selecting channel(s) to filter	74
3.12.2 Other filters	75
3.13 Channel object	75
3.13.1 Channel types	75
3.13.2 Setting the active channel	76
3.13.3 Creating new channels	76
3.14 Color objects	77
3.14.1 Setting a Color	77
3.14.2 Getting and converting colors	78
3.14.3 Comparing Colors	79
3.14.4 Getting a Web Safe Color	79
3.15 History object	80
3.15.1 Filling a selection with a history state	81
3.16 Clipboard interaction	81
3.16.1 Copy	81
3.16.2 Copy merged	82
3.16.3 Cut	82
3.16.4 Paste	83
3.16.5 Paste into command	83
3.17 Action Manager scripting	84
3.17.1 Using the Action Manager from JavaScript	84
3.17.2 Using the Action Manager from VBScript	87

Adobe 23101335 Scripting Guide - Page 10

Object inheritance, 2.2.3 Object elements or collections, you use an index. For example

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